1. Field of the Invention
The invention relates to a boundary detection apparatus and a boundary detection method.
2. Description of Related Art
A method of identifying an object from an image is available in the related art. Japanese Patent Application Publication No. 2013-114476 (JP 2013-114476 A), for example, discloses a technique relating to an object identification method in which gradients of surfaces in respective locations of a disparity image serving as an identification subject are determined, a position and a direction of a fold between the surfaces of the disparity image are extracted as feature information of the identification subject from a connection condition of the gradients of the surfaces, and the type of the identification subject is determined on the basis of the extracted feature information.
It is desirable to be able to detect a boundary between step surfaces with a high degree of precision on the basis of a disparity image. For example, a point at which a disparity value varies may be detected as a boundary. In a region captured from afar, however, the disparity value is small. It is therefore difficult in a region captured from afar to extract the point at which the disparity value varies as a boundary with a high degree of precision.